Caliper attachment



Sept. 9 D. E. MCGREEVY 2,357,836

CALIPER' ATTACHMENT Filed Nov. 23, 1942 2 Sheets-Sheet J.

Inventor ,yezawz/sEdwardM 'zeeg By @Mm Sept. 12, 1944. D. E. M GREEVY 2,357,836

CALIPER ATTACHMENT Filed Nov. 23, 1942 2 Sheets-Sheet 2 /Z) K) \I WNW h I622 az'sZZI/rd M reez Int/enter Patented Sept. 12, 1944 UNITED STATES PATENT OFF! r.

2,357,836 CALIPER ATTACHMENT Dennis Edward McGreevy, New Orleans, La. Application November 23, 1942, Serial No. 466,616

1 Claim.

The present invention relates generally to new and useful improvements in calipers, and has for its primary object to provide, in a manner as hereinafter set forth, an attachment for an instrument of this character comprising novel means whereby fine measurements may be expeditiously made and accurately read.

Another very important object of the invention is to provide an attachment of the aforementioned character which is adapted to be mounted for use on different sizes of calipers.

Other objects of the invention are to provide a caliper attachment of the character described which will be comparatively simple in construction, strong, durable, highly eflicient and reliable in use, compact, and which may be manufactured at low cost.

All of the foregoing and still further objects and advantages of the invention will become apparent from a study of the following specification, taken in connection with the accompanying drawings wherein like characters of reference designate corresponding parts throughout the several views, and wherein:

Figure 1 is a view in front elevation of an attachment constructed in accordance with the present invention mounted on a caliper.

Figure 2 is an elevational view, looking at one side of the device. 7

Figure 3 is an elevational view, looking at the opposite side of the device from the line 33 of Figure 1.

Figure 4 is a view in end elevation of the attachment.

Figure 5 is a view in rear elevation. of the device.

Figure 6 is a cross sectional view, taken substantially on the line 66 of Figure 1.

Figure 7 is a detail view in section, taken substantially on the line 'I'I of Figure 6.

Referring now to the drawings in detail, it will be seen that the embodiment of the invention which has been illustrated comprises an elongated, substantially tapered, longitudinally curved plate i of suitable material, said plate being of the shape shown to advantage in Figure 5 of the drawings. Extending into the plate I from an intermediate point in the outwardly curved outer edge thereof, to a point adjacent its forward end, is an arcuate socket 2. The socket 2 is for the reception of the free end portion of one of the legs 3 of a conventional caliper 4. Screws 5 removably secure the plate I in position on the caliper 4.

On its forward end, the plate I is formed to provide an integral, transversely extending tubu- ,work in an obvious manner.

lar bearing 6. Slidably mounted in the bearing 6 is a work engaging contact "I. The contact 1 includes a head 8 on one end. An extension contact 9 is removably mounted on the free end portion of the other leg I 0 of the caliper 4 in opposed relation to the slidable contact I.

Projecting from the plate I at an intermediate point is a pin I I having a, threaded socket I2 extending thereinto from one end thereof. J ournaled at an intermediate point on the pin II is a pointer I3. One end of the pointer I3 is cooperable with a scale [4 on the front of the plate I adjacent the bearing 6. Stop pins IS on the plate I positively limit the swinging movement of the pointer I3 in opposite directions.

Mounted for rotary adjustment on the'outer .end of the pin II is a cap I6. A coil spring IT has one end anchored to the cap I6 and its other end anchored to the pointer I3 for returning said pointer to zero on the scale I4. 'A screw I8 is threaded into the socket I2 for securing the cap IS in adjusted position on the pin I I.

Pivotally mounted at an intermediate point, as at I9, on the forward portion of the plate I is a lever 20. One end of the lever 20 is engaged with the head 8 of the slidable contact I for actuation thereby. The other end of the lever 20 is engaged with the end portion of the pointer I3 which is remote from the scale M for swinging said pointer across said scale against the tension of the return spring I].

It is thought that the operation of the attachment will be readily apparent from a consideration of the foregoing. Briefly, the pointer I3 is normally in retracted position, as seen in Figure 1 of the drawings, under the influence of the spring ll, thus yieldinglyholding the slidable contact I in projected position through the medium of the lever 20. The caliper 4 is adjusted and the contacts I and 9 are engaged with the As the instrument is moved on the work any variations in the measurement will be clearly indicated by the pointer I3. When the contact I is moved outwardly in the bearing 6, the lever 20 swings the pointer I3 across the scale I4 against the tension of the spring I1. Of course, when the instrument is disengaged from the work, the elements I, 20 and I 3 are returned to the position of Figure 1 of the drawings by the spring I'I. By simply loosening the screw I8, the cap I6 ma be rotatably adjusted to regulate 'the tension of the coil spring I1 as desired.

Secured by bolts Z I on the back of the plate I is a plate 22. The elements 2| and 22 constitute means for clamping the plate I on the caliper in the event that said caliper will not fit in the slot or socketZ. That is, the leg of the Caliper on which the attachment is .to be mounted is inserted between the plates l and 22; after which the bolts 2| are tightened. The head 8 of the slidable contact 1 is engaged with a pin 23 which projects from one end of the lever 20.

It is believed that the many advantages of a caliper attachment constructed in accordance with the present invention will be readily understood, and although a preferred embodiment of the device is as illustrated and described, it is to be understood that changes in the details of construction and in the combination and arrangement of parts may be resorted to which will ment of said pointer in one direction, a screw frictionally securing the cap in adjusted position on the pin, and means for actuating the pointer in said one direction against the tension of the spring.

DENNIS EDWARD MCGREEVY. 

